Magnetic circuit-breaker



(No Model.)

W. E. HARRINGTON.

MAGNETIG CIRCUIT BREAKER.

No. 580,277. Patented Apr. 6, 1897.

FIG-j. FIG? Witnesses. nventor.

A Attorney.

UNITED STATES PATENT OFFICE.

IVALTER E. HARRINGTON, OF PHILADELPHIA, PENNSYLVANIA.

MAGNETIC CIRCUIT-BREAKER.

SPECIFICATION forming part of Letters Patent No. 580,277, dated April 6, 1897.

Application filed January 15,1896. Serial No. 575,591. (No model.)

To all whom it may concern.-

Be it known that I, WALTER E. HARRING- TON, a citizen of the United States, residin gin the city and county of Philadelphia, in the State of Pennsylvania, have invented a new and Improved Magnetic Circuit-Breaker, of which the following is a true and exact description, reference bein had to the accompanying drawings, which form a part of this specification.

My invention relates to automatic magnetic circuit-breakers, and has for its object to provide a circuit-breaker in which the cut-out switch will be actuated to sever connection with the circuit in which it is placed with a rapidity bearing an inverse ratio to the amount of excessive current fiowin g through the cir cuit.

A further object of my invention is to dispense with the latching devices generally used to hold the cut-out switch in a closed position and to effect the opening of the switch by the direct action of a magnetic armature brought into operation and moving with a speed proportioned to the amount of excessive current flowing through the switch.

It is well known that electromagnetic apparatus is frequently injured by an excessive flow of current through it, and also with the automatic cut-outs provided to protect the circuits and apparatus connected therewith from the effect of excessive flow are themselves frequently injured or destroyed by the effect of the current, these injurious results being occasioned by the fact that the cut-out switch generally moves to effect the opening of the circuit with a nearly uniform rate of speed, which rate may be quick enough under ordinary conditions, but is too slow to prevent injury to the apparatus when the rate of flow exceeds a certain amount.

Now my invention consists in effecting the opening movement of the cut-out switch by the direct action upon the switch of an armature arranged to move under a determined flow of current and placed under the influence of a magnet the coils of which are in series with the switch, and it will readily be seen that as the rapidity and momentum with which the armature moves is directly propor tioned to the flow of current the rapidity with which it will force the switch out of contact with the circuit-terminals will also be in direct proportion to the flow of current, and consequently the time in which the cut-out is effected will be in inverse proportion to said flow.

In another application, filed December 20, 1895, Serial No. 573,259, I have shown, described, and claimed my invention as applied to the class of magnetic cut-outs in which the magnetic armature acts to trip or disengage a latch by which the switch is held in a closed position. I do not therefore in this application claim specifically the application of my invention to switches provided with latching devices, and I have shown my invention as applied to a switch which closes the circuit to which it pertains by e11- tering cups adapted to contain mercury and in which the continued disengagement of the switch is insured by so balancing the switchlever that its own weight will, when the switch is closed, tend to keep it closed, and when the switch is open, tend to keep it open.

Reference is now had to the drawings which illustrate my invention, and in which Figure 1 is a side elevation of a magnetic circuit-breaker provided with my improvements; Fig. 2, a front elevation thereof; Fig. 3, a plan view thereof, and Fig. 4 a front elevation of a bipolar or double switch.

A indicates the slab to which the cut-out mechanism is secured; I3, a contact piece or clamp to which is fastened one part of the circuit-wire O and to which is also fastened one terminal of an electromagnetic coil C, the other terminal of which is fastened to a clamp 13.

D is a metallic cup having a cavity D adapted to contain mercury and electrically connected with the clamp B.

D is a similar metallic cup connected with the other portion, 0, of the circuit-wire.

F is a switch-lever pivoted at F, having a handle F on one side of the pivot and a switch F, pivotally secured to the switch-lever, 011 the other side of the pivot, having depending arms, as shown, and so arranged that when the handle is moved to close the switch the said depending arms will enter the cavities D and the cups D and D.

F indicates an impact-plate secured to the switch-lever F in position to receive the blow imparted by the magnetic armature. A

Gr is a spring-catch placed to receive the blowof the handle F when the switch is forced open, and it is secured to a portion of the frame H, to which the various parts of the circuit breaker are also secured, and which in turn is fastened to the slab A.

J is a metallic pin entering the top of the magnetic coil 0 and having a head J, which normally lies upon a flange at the top of the coil and directly beneath the magnetic plate F.

L is a magnetic armature or core lying within and under the influence of the coil G and having, as shown, a slot L, through which passes a pin M, by which the core is anchored to the frame H and upon which the core rests in normal position.

L indicates weights by which the core is adjusted to move by any desired current passing through the coil G.

The apparatus shown in Fig. 1- is essentially of the same character, except that it shows the application of my invention to a two-pole switch, the switches (here indicated byf being each pivoted in a block F one of which is secured to each end of a non-conducting bar F carried by the switch-lever F.

O and 0 indicate the positive branch of the circuit, P and P the negative branch, and it will be seen that by the construction illustrated both branches of the circuit are cut out by one movement of the switch-lever and at the same time.

It will be understood that the balance of the switch-lever and its handle are such that when the switch is closed gravity will tend to keep it closed, while when the switch is opened by the action of the armature L striking and raising the pin J the change in position of the handle F will shift the center of gravity to the outside of the pivot F, the effect of which is of course to cause the handle F to fall and the switch-lever F, together with the switch carried thereby, to rise.

It is obvious from what I have already said that the rapidity with which the switch will be lifted out of contact with the mercury in the cups D and D will depend upon the rapidity of motion of the armature-core L, which in turn depends of course upon the flow of current through the coil 0, and therefore the time required to open the switch will be in the inverse ratio to the excessive current flowing through the circuit.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a magnetic circuit-breaker the combination with an electric circuit and a switchlever adapted to close and open said circuit, of a counterbalance rigidly attached to said lever and so constructed and arranged as to tend when the switch is closed to hold it closed and when the switch is opened to carry it away from the cirei'iit-terminals, an electromagnet, the coils of which are in series with the switch and an armature not normally in contact with the switch-lever actuated by said magnetand adapted to move under a predetermined current, arranged. to impinge against the switch-lever and force it in a direction to open the circuit.

2. In a magnetic circuit-breaker the combination with the mercury-cup terminals in a circuit, of a switch-lever carrying a switch the ends of which are adapted to enter the cups and close the circuit, a counterbalance rigidly attached to said lever and so constructed and arranged as to tend when the switch is closed to hold it closed and when the switch is opened to carry it away from the eupterminals, an eleetromagnet the coils of which are in series with the switch, and an armature not normally in contact with the switch-lever actuated by said magnet and adapted to move with a predetermined current. arranged to impinge directly or indirectly against the switch-lever and raise it to open the switch.

XVALTER E. IIIARRINGTON.

Vitnesses:

CHARLES F. ZIEGLER, D. IIAWARTH. 

